Conventional fire hydrants generally comprise a trunk body, a water inlet through which water from a water main is conducted and a water outlet source which generally comprises two discharge outlets in the form of nozzles having removable caps disposed thereon. The water from the water main is prevented from passing through the water inlet by means of a valve disposed in the trunk extending from the head portion of the trunk body. Thus, if it is desired to discharge water from the fire hydrant, all that is required is that the operator unscrew the caps on the discharge outlets and thereafter turn the exterior operating nut extending from the head portion of the trunk body. Unfortunately, these operations can be performed with conventional tools and equipment such as conventional wrenches and the like, thereby affording an opportunity for unauthorized individuals to cause water to be discharged from the fire hydrant. The unauthorized opening of fire hydrants presents a serious problem to municipalities particularly where there already exists a water shortage. This problem becomes particularly serious in hot weather when fire hydrants are used by unauthorized individuals to cool themselves by the normally cool water which discharges from the fire hydrants. During this time, water sheds and reservoirs are receiving the lowest input of water during the year and this drain on the reservoirs is, therefore, undesirable. In addition to water loss by unauthorized use, a secondary effect of such use is a reduction of the pressure in the mains and in the surrounding hydrants. Since hydrants are primarily used for use in fire fighting, this reduction on pressure can have disastrous results during the demand for fire fighting water especially for high structure buildings. Other side effects include physical harm which may be inflicted upon passing pedestrians and motorists as a result of an unauthorized opened fire hydrant.
Many schemes have been proposed to minimize unauthorized use of hydrants so as to prevent waste of water and maintain pressure in the water main and the surrounding system. One approach for providing a tamper proof hydrant required an annular collar to protect the exposed valve operating nut. Another approach requires the designing of the valve operating nut so that special tools have to be used to operate the valve. Other approaches required protective bands secured over the hydrant caps to prevent their removal without a specially designed tool and the use of special types of locked on hydrant caps which again would require special tools or wrenches to remove them.
In all of the above, externally mounted tamper proof devices are used. These visible external devices can be vandalized or subjected to abuse that could render them inoperative and thereby waste precious time when the hydrants have to be inactivated for official use.
Some municipalities have turned to hydrants with only one outlet nozzle on the hydrant trunk, generally the larger nozzle required by "pumper" engines. This has been done to minimize loss of caps and parts, to lower initial manufacturing cost, and due to the declining requirement and use of the smaller nozzle.
It is an object of the present invention to provide a tamper proof fire hydrant that protects the hydrant from unauthorized use.
Another object of the invention is to provide a fire hydrant with an internally mounted valve operating means so that such means will not be exposed and thereby will be protected against being vandalized or other abusive conditions.
Another object of the invention is to provide a fire hydrant with an internally mounted valve operating means that can only be activated using a special cap assembly designed to seat and be secured on one of the nozzles of the fire hydrant.
The foregoing and additional objects will become apparent from the following description.